Monthly Archives: October 2014

Why a Freeze Kills Plants


As nighttime temperatures dip towards freezing, many gardeners are frantically harvesting the last of the garden bounty.   They know that their remaining nights are numbered.  Summer flavors are nearly done.  Tomatoes.   Peppers.  Eggplant.  Squash.   Basil.

Fresh produce from a garden is truly sublime.  The flavors are fresh and vibrant.  They are far superior to the same produce purchased at grocery stores given that most produced has been shipped from quite a distance to reach the store.  As gardeners, we appreciate what we grow and try to extend the season as long as possible.  But in late summer/early fall, we know that the garden’s days are numbered.  At some point, a freeze will hit and as a result, plants will be damaged or if the freeze was hard enough, our garden crops will die.

tomatoes before a freeze

tomatoes before a freeze

The National Weather Service has terminology for conditions that gardeners listen to closely at this time of year.  They are:

  1. Freeze Warning: temperatures will be at or slightly below 32 °F.
  2. Hard Freeze Warning: temperatures will be at or below 28 °F during the growing season.
  3. Frost Advisory: temperatures will be in the 33 °F – 36 °F  range during the growing season with good cooling conditions (clear skies… no clouds and/or a light wind).

But what exactly does a freeze do to plants?  (And for the record, we are talking about annual vegetables crops, not woody perennials nor trees and shrubs.  Think cucumbers.  Summer squash.  Peppers.  And my favorite… tomatoes.)  According to Texas A & M Extension, “As ice crystals form between cells, the water inside the cells is drawn out through the cell walls.  This causes the cells to get smaller.  The resulting pressure and stress may cause the walls to break.  If the temperature drop is sudden and extreme, ice crystals may form inside the cells of some species rupturing the cell protoplasm and killing the cell in this way”.

There is also another way that a plant suffers freeze damage.  When freezing temperatures are reached, ice crystals form in the water between cell walls.  When temperatures rise and the ice begins to thaw, water will return back into the shrunken cell.  If this happens quickly, the cells may burst.  This destroys the cells.  A plant that suffers from freeze damage (or that is killed by a freeze) is typically wilted in appearance with blackened foliage.

In both cases of freeze damage, it is across the entire plant.

freeze damaged tomato plant

freeze damaged tomato plant

When you see the wilted, blackened plant, it is time to start pulling up those plants.  No amount of tender loving care is going to revive them.   The above photo shows a tomato plant the morning following an overnight hard freeze.  Ice crystals formed, cells burst, and the plant died.  The end of the season is inevitable.

A frost, according to University of California Marin Master Gardeners, “…causing ice crystals to form in plant cells.  This makes water unavailable to plant tissues and disrupts the movement of fluids.  Frost-damaged leaves appear water-soaked, shrivel and turn dark brown or black”.  This damage may be across the entire plant or localized in just one area, such as the tips of leaves.

Sure, you may cover plants to try keep them producing longer, but even that won’t last long.  Cooler nights will signal an end to flowering.  Fruit on the vine will ripen more slowly.  Nature is preparing for the freeze.

So take heart gardeners.  Accept freezes (if you live in a region where temperatures dip that low) as a natural part of the garden season.  Pull up the plants.  Prepare the beds for winter.  But rest up and take delight in garden catalogs that will begin to arrive in January.  After all, summer gardening is just one winter away.


A Fall Pest: Grey Aphids


If you grow anything in the brassica family (kale, collard greens brussels sprouts,cabbage, etc…) you have seen them.  Small.  Grey.  In clusters.  Hanging out on the under side of the leaves.  And they tend to make their appearance in late summer, early fall.    What are they?  Grey aphids.

Grey aphids  are also known as cabbage aphids.  If you want to get scientific, they go by Brevicoryne brassicae.  According to the University of California Agriculture & Natural Resources, these pests occur in dense colonies and “prefer to feed on the youngest leaves and flowering parts and are often found deep within the heads of cabbages or brussels sprouts”.  Interestingly, these little critters do not infest noncruciferous crops, so you don’t have to worry about them migrating to your beets or eggplants.  (And for the record, cruciferous crops are kale, collard greens, brussels sprouts, cabbage, etc..).  And if you have ever harvested your brassicas in late summer/early fall, you may have seen the damage done to the leaves: yellowing leaves or curled and mottled leaves.  Aphids do their damage by sucking the plant juices.  And if left unchecked, they can severely stunt the  growth and even delay or prevent flowering of the plant.

grey aphids

grey aphids

Now don’t give up hope.  Grey aphids can be controlled and even eradicated.

Control Methods

  • Natural enemies:  Some of them include parasitic wasps, lady beetles, lacewings, damsel bugs, and syrphid fly larvae.
  • Insecticidal soap, but be careful as the soap can cause leaf damage if applied on a bright, sunny day.
  • Tomato leaf water: Some gardeners have also had success in chopping up tomato leaves and steeping them in water overnight.  The next day, remove the leaves, add a teaspoon or two of dish soap and fill a spray bottle with the tomato leaf infused water, then directly spray the aphids.
  • Onion and garlic water:  Place a small onion and a whole bulb of garlic in a blender with water.  Blend until the mixture is smooth.  Allow to set 4 – 6 hours and strain out the solids.  Fill a spray bottle with remaining liquid and then directly spray the aphids.
  • Remove the infested leaves from the plants.  These leaves can either be destroyed or if you have chickens, feed to your flock.  If you don’t have chickens, you can also compost the leaves.
  • Spray the infested plants with a strong jet of water to knock aphids off the plant.

So if you have grey aphids on your fall brassicas, you can salvage your crops.  Natural predators and organic methods are both effective.  So go ahead select a control.  With some diligence, you can kick the aphids to the curb and enjoy some tasty kale, collard greens brussels sprouts,cabbage, or other brassicas from your fall garden.


20 Homestead Activities to Share with Young Children


People around the country are returning to their roots.  They are becoming modern homesteaders and joining the legion of others who want to cook meals from scratch, garden organically, raise backyard chickens, and learn the art of preserving.  But much as we are returning to our roots, what about the next generation?  Are we encouraging our children to become homesteaders or sharing with them the very delights we are experiencing?

Regarding if you began homesteading last month or have been at it for years, the key is to share the experience with your children.  Get them involved and share tasks so they have a better understanding of what you do on a daily or weekly basis.   You just be the inspiration for the next generation of modern/urban homesteaders.

To get your children engaged, think about their age.  What they are capable of?  What have they shown interest in?  Do they have the manual dexterity for certain tasks?  Have they asked to help?

photo by April Sorrow

photo by April Sorrow

20 Homestead Skills to Share with Young Children

  1. Hang laundry to dry (can hang clothes on a drying rack if clothes line is too high for them to reach).
  2. Feed small animals such as rabbits, chickens, and ducks.
  3. Gather eggs from the nest boxes (if you have a lot of chickens, allow them to make multiple trips to the coop).
  4. Take them seed shopping or show them the catalogs and read the descriptions to them (buy some items they are interested in).
  5. Bring in kindling for the fireplace.
  6. Add material to nest boxes.
  7. Give them a small garden bed (or planters or containers) to help tend during the garden season.
  8. Purchase child-sized tools and show them how to properly use the tools (many nurseries or online garden stores now offer small tools for children, such as hoes, rakes, and watering cans).
  9. Teach them when various fruits and vegetables are ripe and when to harvest (allow them to sample as they harvest).
  10. Allow them to help pick the chicks, ducklings, or rabbits that you will raise.
  11. Teach them how to cook (start with easy projects such as measuring ingredients, how to mix, and how to follow a recipe).
  12. Have them help wash fruits and vegetables after harvesting (show them how dirt sinks to the bottom of the sink or bucket).
  13. Show them how you mend cloths: sewing on a button, darning socks, sewing on a patch, etc…
  14. Explain how composting is plant recycling and have them add materials to your compost bucket/bin/pile.
  15. Show them how to gather seeds at the end of the season (make sure to gather just one variety at a time and then how to separate seed from any pod or chaff and how to dry if necessary.  Use plain envelopes and allow them to decorate the packets.
  16. Show them how to wash dishes (save the sharp knives for yourself) and how a clean dish should feel… no grit or food residue stuck to it.
  17.  Teach them how to plant seedlings as well as seeds.  Allow them to dig the furrow or hole with their own garden tool.
  18. Have them help rake and gather leaves.  Let the experience be fun and allow time for jumping into piles of leaves.
  19. Show them how to press leaves and flowers.  When they are dry, your children can create their own craft project to decorate their room or perhaps to adorn the refrigerator.  (Paper and glue are great starting points).
  20. Ask them to get canning jars (one or two at a time) in the size you need (such as half pints, pints, quarts) for canning projects plus lids and rims.  Take this opportunity to explain why and how to can.

By involving your child(ren) in homesteading projects, you are teaching them valuable skills.  They learn the hows and whys.  They may experience some disappointments, but will discover that is part of the process.  When things go well, they will feel a sense of accomplishment.  They can point to something and say, “I did that”!  If you have more than one child, they will learn how to work together.  What a bonus!

For the best possible experience for your child, start small.  Don’t overwhelm them with tasks or complicated procedures.  Keep their safety in mind.  Don’t have them do a chore or task that could put them at risk for harm.  By keeping these things in mind, not only can you educate your little ones about homesteading, but get them involved so they truly feel part of the daily/weekly activities.  You just may be raising the next generation of homesteaders!

photo credit: <a href=””>UGA College of Ag & Environmental Sciences – OCCS</a> via <a href=””>photopin</a&gt; <a href=””>cc</a&gt;